18684812089 has 2 divisors, whose sum is σ = 18684812090. Its totient is φ = 18684812088.

The previous prime is 18684811963. The next prime is 18684812099. The reversal of 18684812089 is 98021848681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13914561600 + 4770250489 = 117960^2 + 69067^2 .

It is an emirp because it is prime and its reverse (98021848681) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18684812089 - 2²³ = 18676423481 is a prime.

It is not a weakly prime, because it can be changed into another prime (18684812099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9342406044 + 9342406045.

It is an arithmetic number, because the mean of its divisors is an integer number (9342406045).

Almost surely, 2^18684812089 is an apocalyptic number.

It is an amenable number.

18684812089 is a deficient number, since it is larger than the sum of its proper divisors (1).

18684812089 is an equidigital number, since it uses as much as digits as its factorization.

18684812089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1769472, while the sum is 55.

The spelling of 18684812089 in words is "eighteen billion, six hundred eighty-four million, eight hundred twelve thousand, eighty-nine".